Conventional systems for controlling lighting in homes and other buildings suffer from many drawbacks. One such drawback is that these systems rely on conventional lighting technologies, such as incandescent bulbs and fluorescent bulbs. Such light sources are limited in many respects. For example, such light sources typically do not offer long life or high energy efficiency. Further, such light sources offer only a limited selection of colors, and the color or light output of such light sources typically changes or degrades over time as the bulb ages. In systems that do not rely on conventional lighting technologies, such as systems that rely on light emitting diodes (“LEDs”), long system lives are possible and high energy efficiency can be achieved. However, in such systems issues with color quality can still exist.
A light source can be characterized by its color temperature and by its color rendering index (“CRI”). The color temperature of a light source is the temperature at which the color of light emitted from a heated black-body radiator is matched by the color of the light source. For a light source which does not substantially emulate a black body radiator, such as a fluorescent bulb or an LED, the correlated color temperature (“CCT”) of the light source is the temperature at which the color of light emitted from a heated black-body radiator is approximated by the color of the light source. The CRI of a light source is a measure of the ability of a light source to reproduce the colors of various objects faithfully in comparison with an ideal or natural light source. The CCT and CRI of LED light sources is typically difficult to tune and adjust. Further difficulty arises when trying to maintain an acceptable CRI while varying the CCT of an LED light source and while dimming the intensity level of the LED light source from full intensity to an off condition when no light is emitted at all.